On June 6, 1942, Japanese forces invaded the island of Kiska and on June 7, the island of Attu. These islands are the western most island on the Aleutian chain and are part of Alaska. The U.S. feared that the islands would be used as bases from which to launch aerial assaults against the West Coast, and it became a matter of national pride to expel the first invaders to set foot on American soil since the War of 1812.

After Martinez completed his basic training, he was assigned to Company K, 32d Infantry, 7th Infantry Division. The 7th Infantry Division landed at Holtz Bay, Attu. On May 26, 1943, 32nd Infantry Regiment was engaged in combat in the vicinity of Fish Hook Ridge against enemy troops. The regiment was pinned down by enemy fire and Martinez on his own account led two assaults. He fired rifle into the Japanese foxholes and the men of his unit followed. Martinez was shot in the head as he approached one final foxhole after the second assault, dying of the wound the following day. Martinez was posthumously awarded the Medal of Honor.

Private Martinez was the first Hispanic-American recipient who was posthumously awarded the Medal of Honor for combat heroism on American soil during World War II.[4]

[Martinez was buried with full military honors at Ault Cemetery, Ault, Weld County in Colorado. On April 13, 1945, the United States Navy named one of its ships, which served as a troop transport during the Korean War, the USNSPrivate Joe P. Martinez. The state of Colorado has honored his memory by naming a street and renaming a former base reception center and early officer’s club which currently serves as the service center after him. The government named a Disabled American Veterans chapter in Colorado and an American Legion post in California in his honor. Three statues were erected with his likeness and are located in the Colorado cities of Ault, Greeley and Denver. The U.S. Army also named an Army Reserve military installation in Denver, Colorado after Martinez.[6] The 7th Infantry Division honored him by naming the Fort Ord Welcome Center (originally the Post Headquarters built in 1941)Martinez Hall in 1977. Although Fort Ord closed in 1993, Martinez Hall still serves as a Veterans Transition Service Center.

The President of the United Statesin the name of The Congresstakes pleasure in presenting theMedal of Honorto

Citation: For conspicuous gallantry and intrepidity above and beyond the call of duty in action with the enemy. Over a period of several days, repeated efforts to drive the enemy from a key defensive position high in the snow-covered precipitous mountains between East Arm Holtz Bay and Chichagof Harbor had failed. On 26 May 1943, troop dispositions were readjusted and a trial coordinated attack on this position by a reinforced battalion was launched. Initially successful, the attack hesitated. In the face of severe hostile machinegun, rifle, and mortar fire, Pvt. Martinez, an automatic rifleman, rose to his feet and resumed his advance. Occasionally he stopped to urge his comrades on. His example inspired others to follow. After a most difficult climb, Pvt. Martinez eliminated resistance from part of the enemy position by BAR fire and hand grenades, thus assisting the advance of other attacking elements. This success only partially completed the action. The main Holtz-Chichagof Pass rose about 150 feet higher, flanked by steep rocky ridges and reached by a snow-filled defile. Passage was barred by enemy fire from either flank and from tiers of snow trenches in front. Despite these obstacles, and knowing of their existence, Pvt. Martinez again led the troops on and up, personally silencing several trenches with BAR fire and ultimately reaching the pass itself. Here, just below the knifelike rim of the pass, Pvt. Martinez encountered a final enemy-occupied trench and as he was engaged in firing into it he was mortally wounded. The pass, however, was taken, and its capture was an important preliminary to the end of organized hostile resistance on the island.